Performance Enhancement on PS Data-Off

ABSTRACT

A method of modifying PS_Data_Off status via a PDN connection modification procedure and interpreting network PS_Data_Off support feature is proposed. A UE modifies the PS data off status by using a bearer resource modification procedure. The UE receives a response to the modification request and monitors whether the response includes the 3GPP PS_Data_Off Support indication. In one embodiment, if the network does not provide the 3GPP PS_Data_Off Support Indication, the UE thinks that the network does not support PS data off feature regardless whether the network accept or reject the modification request. In another embodiment, if the network does not provide the 3GPP PS_Data_Off Support Indication, then UE thinks that the network supports PS data off feature if it accepts the modification request, and does not support PS data off feature if it rejects the modification request.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 from U.S. Provisional Application No. 62/670,629, entitled “Performance Enhancement on 5GSM”, filed on May 11, 2018, the subject matter of which is incorporated herein by reference.

TECHNICAL FIELD

The disclosed embodiments relate generally to wireless communication, and, more particularly, to method of supporting enhanced PS domain data-off mechanism in next generation mobile communication systems.

BACKGROUND

The wireless communications network has grown exponentially over the years. A Long-Term Evolution (LTE) system offers high peak data rates, low latency, improved system capacity, and low operating cost resulting from simplified network architecture. LTE systems, also known as the 4G system, also provide seamless integration to older wireless network, such as GSM, CDMA and Universal Mobile Telecommunication System (UMTS). In LTE systems, an evolved universal terrestrial radio access network (E-UTRAN) includes a plurality of evolved Node-Bs (eNodeBs or eNBs) communicating with a plurality of mobile stations, referred to as user equipments (UEs). The 3^(rd) generation partner project (3GPP) network normally includes a hybrid of 2G/3G/4G systems. With the optimization of the network design, many improvements have developed over the evolution of various standards.

LTE networks are packet-switched (PS) IP networks. This means that the networks deliver all data traffic in IP packets, and provide users with Always-On IP Connectivity. When UE joins an LTE network, a Packet Data Network (PDN) address (i.e., the one that can be sued on the PDN) is assigned to the UE for its connection to PDN. LTE calls the users “IP access connection” an evolved packet system (EPS) bearer, which is a connection between the UE and the PDN gateway (P-GW). The P-GW is the default gateway for the UEs IP access. LTE has defined a Default EPS Bearer to provide the Always-On IP Connectivity. By introducing Always-On IP Connectivity in 3GPP network, it became difficult for the subscriber to have explicit control of the traffic sent or received by its UE, which could lead to unexpected charging.

3GPP PS_Data_Off feature is thus introduced to meet the requirements. The PS_Data_Off feature prevents transport via 3GPP access of all IP packets except those related to 3GPP PS_Data_Off Exempt services. The UE discovers a P-GW supports 3GPP PS_Data_Off feature at initial attach and during the establishment of a PDN connection via the presence of the 3GPP PS_Data_Off Support indication in the Create Session response message. When the UE requests a new PDN connectivity, the UE shall include the indication in the PCO within the PDN Connectivity Request message. When the UE changes its PS_Data_Off status, the UE shall report a change of its 3GPP PS Data Off status in PCO by using Bearer Resource Modification procedure. For IP Multimedia Subsystem (IMS) services, the UE shall inform the IMS domain in initial REGISTER request and subsequent re-REGISTER request for the status change.

However, when UE modifies the PS Data Off status by using the Bearer Resource Modification procedure, the network may either accept or reject the modification request, and the network may or may not include the 3GPP PS_Data_Off Support Indication when accept or reject the modification request. The UE interpretation and behavior are undefined under those circumstances. A solution is sought.

SUMMARY

A method of modifying PS_Data_Off status via a PDN connection modification procedure and interpreting network PS_Data_Off support feature is proposed. A UE establishes a PDN connection with the network and receives a PS_Data_Off support indication indicating that the network support PS_Data_Off feature. The UE later modifies the PS data off status by using a bearer resource modification procedure. The UE receives a response to the modification request and monitors whether the response includes the 3GPP PS_Data_Off Support indication. In one embodiment, if the network does not provide the 3GPP PS_Data_Off Support Indication, the UE thinks that the network does not support PS data off feature regardless whether the network accept or reject the modification request. In another embodiment, if the network does not provide the 3GPP PS_Data_Off Support Indication, then UE thinks that the network supports PS data off feature if it accepts the modification request, and does not support PS data off feature if it rejects the modification request. The reject message can carry an ESM cause value, e.g., PS data off not supported. In yet another embodiment, if the network provides the 3GPP PS_Data_Off Support Indication, then the indication explicitly indicates whether PS data off feature is supported by the network.

In one embodiment, a UE establishes a packet data network (PDN) connection in a mobile communication network. The UE receives a first packet-switched data-off (PS_Data_Off) support indication from the network. The UE transmits a Bearer Resource Modification Request to the network and receiving a response to the Bearer Resource Modification Request from the network. The UE monitors a second PS_Data_Off support indication in the response to the Bearer Resource Modification Request. The UE determines whether PS_Data_Off is supported by the network upon detecting whether the response to the Bearer Resource Modification Request carries any PS_Data_Off support indication.

In another embodiment, a UE establishes a packet data network (PDN) connection in a mobile communication network. The UE receives a Modify EPS Bearer Context Request message from the network. The UE monitors a packet-switched data-off (PS_Data_Off) support indication in the Modify EPS Bearer Context Request message. The UE determines whether PS_Data_Off is supported by the network upon detecting whether the Modify EPS Bearer Context Request message carries any PS_Data_Off support indication.

Other embodiments and advantages are described in the detailed description below. This summary does not purport to define the invention. The invention is defined by the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, where like numerals indicate like components, illustrate embodiments of the invention.

FIG. 1 illustrates an exemplary LTE network with supporting enhanced PS domain data-off mechanism in accordance with one novel aspect.

FIG. 2 illustrates simplified block diagrams of a user equipment (UE) in accordance with embodiments of the current invention.

FIG. 3 illustrates a first embodiment of a sequence flow of a PDN connection establishment procedure and a PDN connection modification procedure supporting PS_Data_Off in accordance with embodiments of the current invention.

FIG. 4 illustrates a second embodiment of a sequence flow of a PDN connection establishment procedure and a PDN connection modification procedure supporting PS_Data_Off in accordance with embodiments of the current invention.

FIG. 5 is a flow chart of a method of supporting PS_Data_Off configuration and reconfiguration in accordance with one novel aspect.

FIG. 6 is a flow chart of a method of supporting PS_Data_Off configuration and reconfiguration in accordance with one novel aspect.

DETAILED DESCRIPTION

Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

FIG. 1 illustrates an exemplary LTE network 100 with supporting enhanced PS domain data-off mechanism in accordance with one novel aspect. LTE network 100 comprises application servers including an IP multimedia subsystem (IMS) server 111 that provides various services by communicating with a plurality of user equipments (UEs) including UE 114. In FIG. 1, IMS server 111 and a packet data network gateway (PDN GW or P-GW) 113 belong to part of a core network CN 110. UE 114 and its serving base station BS 115 belong to part of a radio access network RAN 120. RAN 120 provides radio access for UE 114 via a radio access technology (RAT). IMS server 111 communicates with UE 114 through PDN GW 113, serving GW 116, and BS 115. A mobility management entity (MME) 117 communicates with BS 115, serving GW 116 and PDN GW 113 for mobility management of wireless access devices in LTE network 100. UE 114 may be equipped with a single radio frequency (RF) transceiver or multiple RF transceivers for services via different RATs/CNs. UE 114 may be equipped with a single Subscriber Identification Module (SIM) or multiple SIMs. UE 114 may be a smart phone, a wearable device, an Internet of Things (IoT) device, a tablet, etc.

LTE networks are packet-switched (PS) IP networks. This means that the networks deliver all data traffic in IP packets, and provide users with Always-On IP Connectivity. When UE joins an LTE network, a Packet Data Network (PDN) address (i.e., the one that can be sued on the PDN) is assigned to the UE for its connection to the PDN. LTE calls the UE's “IP access connection” an evolved packet system (EPS) bearer, which is a connection between the UE and the P-GW. The P-GW is the default gateway for the UE's IP access. LTE has defined a Default EPS Bearer to provide the Always-On IP Connectivity. By introducing Always-On IP Connectivity in 3GPP network, it became difficult for the subscriber to have explicit control of the traffic sent or received by its UE, which could lead to unexpected charging. 3GPP PS_Data_Off feature is thus introduced to meet the requirements. The PS_Data_Off feature, when active, prevents transport via 3GPP access of all IP packets in both uplink and downlink except those related to 3GPP PS_Data_Off Exempt Services. UEs are configured with a default list of 3GPP PS_Data_Off Exempt Services (e.g., in its universal subscriber identification module (USIM) or management object (M)).

The UE discovers a P-GW supports 3GPP PS_Data_Off feature at initial attach and during the establishment of a PDN connection via the presence of the 3GPP PS_Data_Off Support Indication in the Create Session response message. When the UE requests a new PDN connectivity, the UE shall include the indication in the PCO within the PDN Connectivity Request message. When the UE changes its PS_Data_Off status, the UE shall report a change of its 3GPP PS Data Off status in PCO by using Bearer Resource Modification procedure. For IP Multimedia Subsystem (IMS) services, the UE shall inform the IMS domain in initial REGISTER request and subsequent re-REGISTER request for the status change. However, when UE modifies the PS Data Off status by using the Bearer Resource Modification procedure, the network may either accept or reject the modification request, and the network may or may not include the 3GPP PS_Data_Off Support Indication when accept or reject the modification request. The UE interpretation and behavior are undefined under those circumstances.

In accordance with one novel aspect, a method of modifying PS_Data_Off status via a PDN connection modification procedure and interpreting network PS_Data_Off support feature is proposed. In the example of FIG. 1, UE 114 established a PDN connection 130 with the network and receives a PS_Data_Off support indication indicating that the network support PS_Data_Off feature. As depicted by 140, UE 114 later modifies the PS data off status by using a bearer resource modification procedure. UE 114 receives a response to the modification request and monitors whether the response includes the 3GPP PS_Data_Off Support Indication. In one embodiment, if the network does not provide the 3GPP PS_Data_Off Support Indication, then UE 114 thinks that the network does not support PS data off feature regardless whether the network accept or reject the modification request. In another embodiment, if the network does not provide the 3GPP PS_Data_Off Support indication, then UE 114 thinks that the network supports PS data off feature if it accepts the modification request, and does not support PS data off feature if it rejects the modification request. The reject message can carry an ESM cause value, e.g., PS data off not supported. In yet another embodiment, if the network provides the 3GPP PS_Data_Off Support Indication, then the indication explicitly indicates whether PS data off feature is supported by the network.

FIG. 2 illustrates simplified block diagrams of a terminal equipment TE 200 and a mobile terminal MT 250 in accordance with embodiments of the current invention. TE 200 comprises a processor 201, memory 202, and protocol stacks 210 including Application (APP) layer, Transport (TCP/UDP) layer, Network (IP) layer, Data Link layer, Physical (PHY) layer, and radio interface. TE 200 further comprises system control modules 220 including a user interface, a configuration and control module, a connection handler, a PS Data module, a handover module, a cell reselection module, and a telephony circuit. Processor 201 processes different applications and invokes different system control modules to perform various features of TE 200. Memory 202 stores program instructions and data 203 to control the operations of TE 200. The system control modules and circuits that can be implemented by software, firmware and/or hardware, and configured to carry out functional tasks of TE 200.

For IP data service, TE 200 establishes one or multiple PDN connections to its target PDN. Upon PDN connection establishment, application data needs to be encapsulated and segmented at each layer, from higher layer to lower layer (e.g., TCP→IP→Data Link), and then transmitted in the PHY layer. The above functionalities are handled by the connection handler, the PS data controller, the handover module, and the cell reselection module, together with the protocol stacks 210. Typically, TE 200 is also equipped with telephony framework circuits (e.g., a dialer, a call manager etc.) to support voice call functionality. In addition, TE 200 also supports the AT commands as defined by 3GPP TS27.007 for controlling MT functions and GPRS Packet domain services based on PDP contexts, which includes PS_Data_Off configuration for each of the established PDN connections.

MT 250 has an antenna 256, which transmits and receives radio signals. A RF or dual-RF transceiver module 254, coupled with the antenna, receives RF signals from antenna 256, converts them to baseband signals and sends them to processor 251 via baseband or dual-BB module 255. RF transceiver 254 also converts received baseband signals from processor 251 via baseband module 255, converts them to RF signals, and sends out to antenna 256. Processor 251 processes the received baseband signals and invokes different functional modules to perform features in MT 250. Memory 252 stores program instructions and data 253 to control the operations of MT 250.

MT 250 also comprises a set of protocol stacks 260 and control circuits including various system modules 270 to carry out functional tasks of MT 250. Protocol stacks 260 comprises Non-Access-Stratum (NAS) layer, Radio Resource Control (RRC) layer, Packet Data Convergence Protocol/Radio Link Control (PDCP/RLC) layer, Media Access Control (MAC) layer, and Physical (PHY) layer. System modules 270 comprises a configuration and control module, a PS Data module for setting and reporting PS_Data_Off configuration, a SIM/USIM or dual SIM/USIM card, and a MO module. In the example of FIG. 2, MT 250 further comprises a Terminal Adaptor (TA 280) that receives and transmits AT commands and converts the AT commands to be processed by processor 251 for controlling MT functions. In one example, TA 280 receives an AT read command from a TE for the MT to retrieve PS_Data_Off configuration from the network. In another example, TA 280 receives an AT set command from a TE for changing PS_Data_Off configuration and send indication to the network.

The various function modules and control circuits of TE 200 and MT 250 may be implemented and configured by software, firmware, hardware, and/or combination thereof. The function modules and circuits, when executed by the processors via program instructions contained in the memory, interwork with each other to allow the base station and UE to perform embodiments and functional tasks and features in the network. In one example, each module or circuit comprises a processor (e.g., 201 or 251) together with corresponding program instructions. In one example, a UE comprises both TE 200 and MT 250. UE monitors PS_Data_Off support indication from the network and determines whether PS_Data_Off is supported via a bearer resource modification procedure.

FIG. 3 illustrates a first embodiment of a sequence flow of a PDN connection establishment procedure and a PDN connection modification procedure supporting PS_Data_Off in accordance with embodiments of the current invention. In step 311, UE 301 sends a PDN connectivity request to network 302 to establish a PDN connection. The establishment request includes a PS_Data_Off status indication of the UE. In step 312, UE 301 receives an activate default EPS bearer context request from the network. In one example, the activation request includes a PS_Data_Off support indication of the network, indicating that PS_Data_Off is supported. In step 313, UE 301 changes its PS_Data_Off status. When PS_Data_Off status is changed by the UE, UE needs to inform the network about the latest PS_Data_Off status. In step 321, UE 301 initiates a PDN connection modification procedure by sending a bearer resource modification request to the network. The modification request includes an updated PS_Data_Off status indication of the UE. In step 322, UE 301 receives a response from the network. If the network accepts the modification request, then the response is a modify EPS bearer context request message. If the network rejects the modification request, then the response is a modify EPS bearer context reject message. In either case, the response may or may not provide any PS_Data_Off support indication to the UE.

In step 323, UE 301 monitors whether the response carries any PS_Data_Off support indication and determines whether PS_Data_Off support is supported or not. In one embodiment, if the network does not provide the PS_Data_Off Support Indication, then UE 301 thinks that the network does not support PS data off feature regardless whether the network accept or reject the modification request. In another embodiment, if the network does not provide the PS_Data_Off Support Indication, then. UE 301 thinks that the network supports PS data off feature if it accepts the modification request, and does not support PS data off feature if it rejects the modification request. The reject message can carry an ESM cause value, e.g., PS data off not supported. In yet another embodiment, if the network provides the 3GPP PS_Data_Off Support Indication, then the indication explicitly indicates whether PS data off feature is supported by the network. In step 331, if UE 301 determines that PS_Data_Off is not supported, then UE 301 will not inform the network any PS_Data_Off status change of the UE.

FIG. 4 illustrates a second embodiment of a sequence flow of a PDN connection establishment procedure and a PDN connection modification procedure supporting PS_Data_Off in accordance with embodiments of the current invention. In step 411, UE 401 and network 402 establish a PDN connection. In one example, the PDN connection does not support PS_Data_Off. In step 412, network 402 sends a modify EPS bearer context request to UE 401. The request includes a PS_Data_Off support indication. In step 413, UE 401 monitors the PS_Data_Off support indication and knows that PS_Data_Off is now supported by the network. In step 414, UE 401 changes its PS_Data_Off status. When PS_Data_Off status is changed by the UE, UE needs to inform the network about the latest PS_Data_Off status when PS_Data_Off is supported by the network. As a result, UE initiates a PDN connection modification procedure, and steps 421 to 423 are similar to steps 321 to 323 of the embodiments in FIG. 3.

FIG. 5 is a flow chart of a method of supporting PS_Data_Off configuration and reconfiguration in accordance with one novel aspect. In step 501, a UE establishes a packet data network (PDN) connection in a mobile communication network. The UE receives a first packet-switched data-off (PS_Data_Off) support indication from the network. In step 502, the UE transmits a Bearer Resource Modification Request to the network and receiving a response to the Bearer Resource Modification Request from the network. In step 503, the UE monitors a second PS_Data_Off support indication in the response to the Bearer Resource Modification Request. In step 504, the UE determines whether PS_Data_Off is supported by the network upon detecting whether the response to the Bearer Resource Modification Request carries any PS_Data_Off support indication.

FIG. 6 is a flow chart of a method of supporting PS_Data_Off configuration and reconfiguration in accordance with one novel aspect. In step 601, a UE establishes a packet data network (PDN) connection in a mobile communication network. In step 602, the UE receives a Modify EPS Bearer Context Request message from the network. In step 603, the UE monitors a packet-switched data-off (PS_Data_Off) support indication in the Modify EPS Bearer Context Request message. In step 604, the UE determines whether PS_Data_Off is supported by the network upon detecting whether the Modify EPS Bearer Context Request message carries any PS_Data_Off support indication.

Although the present invention has been described in connection with certain specific embodiments for instructional purposes, the present invention is not limited thereto. Accordingly, various modifications, adaptations, and combinations of various features of the described embodiments can be practiced without departing from the scope of the invention as set forth in the claims. 

What is claimed is:
 1. A method, comprising: establishing a packet data network (PDN) connection by a user equipment (UE) in a mobile communication network, wherein the UE receives a first packet-switched data-off (PS_Data_Off) support indication from the network; transmitting a Bearer Resource Modification Request to the network and receiving a response to the Bearer Resource Modification Request from the network; monitoring a second PS_Data_Off support indication in the response to the Bearer Resource Modification Request; and determining whether PS_Data_Off is supported by the network upon detecting whether the response to the Bearer Resource Modification Request carries any PS_Data_Off support indication.
 2. The method of claim 1, wherein the UE triggers the PDU session modification request by modifying a PS_Data_Off status of the UE.
 3. The method of claim 1, wherein the UE determines that PS_Data_Off is not supported by the network when the response does not carry any PS_Data_Off support indication.
 4. The method of claim 3, wherein the Bearer Resource Modification Request is accepted via a Modify EPS Bearer Context Request message.
 5. The method of claim 3, wherein the Bearer Resource Modification Request is rejected via a Modify EPS Bearer Context Reject message.
 6. The method of claim 5, wherein the Modify EPS Bearer Context Reject message comprises a proper cause sent to the UE.
 7. The method of claim 1, wherein the UE receives the second PS_Data_Off support indication in the response to the Bearer Resource Modification Request.
 8. The method of claim 7, wherein the PS_Data_Off support indication comprises a field indicating whether PS_Data_Off is supported or not.
 9. The method of claim 1, wherein the UE determines whether to inform a subsequent PS_Data_Off status change to the network based on whether PS_Data_Off is supported by the network.
 10. A User Equipment (UE), comprising: a connection handling circuit that establishes a packet data network (PDN) connection in a mobile communication network, wherein the UE receives a first packet-switched data-off (PS_Data_Off) support indication from the network; a transmitter that transmits a Bearer Resource Modification Request to the network, wherein the UE receives a response to the Bearer Resource Modification Request from the network; a monitoring circuit that monitors a second PS_Data_Off support indication in the response to the Bearer Resource Modification Request; and a PS data handling circuit that determines whether PS_Data_Off is supported by the network upon detecting whether the response to the carries any PS_Data_Off support indication.
 11. The UE of claim 10, wherein the UE triggers the PDU session modification request by modifying a PS_Data_Off status of the UE.
 12. The UE of claim 10, wherein the UE determines that PS_Data_Off is not supported by the network when the response does not carry any PS_Data_Off support indication.
 13. The UE of claim 12, wherein the Bearer Resource Modification Request is accepted via a Modify EPS Bearer Context Request message.
 14. The UE of claim 12, wherein the Bearer Resource Modification Request is rejected via a Modify EPS Bearer Context Reject message.
 15. The UE of claim 14, wherein the Modify EPS Bearer Context Reject message comprises a proper cause sent to the UE.
 16. The UE of claim 10, wherein the UE receives the second PS_Data_Off support indication in the response to the Bearer Resource Modification Request.
 17. The UE of claim 16, wherein the PS_Data_Off support indication comprises a field indicating whether PS_Data_Off is supported or not.
 18. The UE of claim 10, wherein the UE determines whether to inform a subsequent PS_Data_Off status change to the network based on whether PS_Data_Off is supported by the network.
 19. A method comprising: establishing a packet data network (PDN) connection by a user equipment (UE) in a mobile communication network; receiving a Modify EPS Bearer Context Request message from the network; monitoring a packet-switched data-off (PS_Data_Off) support indication in the Modify EPS Bearer Context Request message; and determining whether PS_Data_Off is supported by the network upon detecting whether the Modify EPS Bearer Context Request message carries any PS_Data_Off support indication.
 20. The method of claim 19, wherein the PDN connection does not support PS_Data_Off before the Modify EPS Bearer Context Request message is transmitted from the network.
 21. The method of claim 20, wherein the Modify EPS Bearer Context Request message carries the PS_Data_Off support indication indicating PS_Data_Off is supported by the network.
 22. The method of claim 21, wherein the UE determines whether to inform a subsequent PS_Data_Off status change to the network based on whether PS_Data_Off is supported by the network. 